This lesson will identify, describe and differentiate the primary motor cortex, prefrontal cortex, and association areas of the frontal lobe. The functions and problems that may be associated with the frontal lobes will be discussed. The contribution of Phineas Gage's accident to the field of psychology will be explored.
Welcome to today's lesson on the cerebral cortex and frontal lobe. In this lesson you're going to learn about functions and problems that may be associated with the frontal lobe, and the contribution of Phineas Gage's accident to the field of psychology.
This tutorial will cover the following in-depth:
The brain is divided into two hemispheres, then further subdivided into 4 sections, also called lobes. There's the frontal lobe, the parietal lobe, the temporal lobe, and the occipital lobe. Each lobe, and different area, is related to a different type of behavior, or different mental processes. This is what we refer to as localization of function.
The frontal lobe is related to lots of different mental processes and functions that we recognize as being uniquely human. These are things like the control of our movement of our bodies, our long-term memories, planning, reasoning, and even judgment.
Research exploring damage to the frontal lobe has proven to assist in the discovery of the impact in which the front lobe has on changes of an individual's personality and behavior.
A famous psychological case involves studying a man who survived an accident whereby a tamping rod (a long thin rod with a spike on one end) went through his brain, causing severe damage.
In 1848, this rod sliced through the brain of Phineas Gage, specifically through the frontal lobe, the prefrontal cortex.
His friends noted that there were specific changes within his behavior and his personality. Phineas became a lot more quick-tempered and impatient. He was also very indulgent in things that were less acceptable.
Prior to the accident, Phineas was very hardworking and responsible. However, after the accident he had taken up cursing, drinking, gambling. In addition, there was intellectual damage and he couldn't complete work or plan for things.
This case demonstrated that the frontal lobe must be related to a lot of those behaviors. This led to a lot of the initial development about localization of function, and the different parts of the brain related to different behaviors and processes.
Another aspect of the frontal lobe, and damage to it, is through the surgical procedure called a lobotomy. The frontal lobotomy was popular in the US during the 1940s.
It involved disconnecting or removing certain sections of the prefrontal cortex of the frontal lobe. This was meant to deal with a lot of severe mental disorders, especially in difficult individuals.
A lobotomy created severe changes in a person's activities, and their personality. Individuals were very docile and the surgery often reduced them to a vegetable statte; basically comatose. Eventually it was abandoned because of cruelty. Thankfully, new, more humane sorts of procedures, were introduced.
A lobotomy was featured in a famous book and film called, "One Flew Over the Cuckoo's Nest."
The first area to look at in the frontal lobe is the prefrontal cortex. The prefrontal cortex is the front-most, foremost part of the frontal lobe. It's basically the first half area of the frontal lobe, going all the way up to the front.
The frontal lobe is responsible for a person's sense of self (e.g., self-awareness, impulse control and emotions). You can see that Phineas Gage and the lobotomy concerns damage specifically to the prefrontal cortex, which lead to changes in personality.
The prefrontal cortex is also related to reasoning and planning. It is responsible for higher level kind of cognitive abilities, specific to humans.
Another area of the frontal lobe to look at includes the association areas, which are the rest of the frontal lobe, moving up towards the parietal lobe. Those areas help to process information, and in the formation of memory, especially a lot of the sensory information that's coming in, is processed in these association areas.
One of these association areas, that's important to language production specifically, is Broca's Area. Broca's Area is named for a French neurosurgeon named Paul Broca.
Dr. Paul Broca noticed that patients with brain damage to this area of the brain were able to understand words, but could not actually produce speech. This is a condition we call Broca's Aphasia, where they are unable to produce speech, even though they know what other people are saying to them.
Specifically, this is trouble with motor production and includes problems with grammar and pronunciation. Any kind of language the person is able to produce is very difficult to understand.
The final area of the frontal lobe to look at is the primary motor cortex, which is this little area that's bordering the parietal lobe. This area in particular is related specifically to movement, and the control of the body's muscles.
The primary motor cortex is arranged in such a way that larger areas of the prefrontal cortex are devoted to more important and specific, or more sensitive, areas of the body.
Hands have a much larger area, because they're very sensitive and we need to manipulate them more closely.The face as well, and the tongue, because those are very sensitive and minute areas that we want to be able to control with a lot of detail.
This tutorial covered the frontal lobe, which is responsible for control of our movement of our bodies, our long-term memories, planning, reasoning, and even judgment. Phineas Gage is a famous psychological study that resulted in damage to a man's prefrontal cortex, but yet he survived. It was noted how his behavior had significantly changed following the accident. A lobotomy was a surgical procedure that involved removing sections of the frontal lobe. The prefrontal cortex is responsible for impulse control and self-awareness. And finally, Broca's Area is related to language.
Source: This work is adapted from Sophia author Erick Taggart.
The foremost part of the frontal lobe, involved with sense of self: awareness, impulse control, emotion.
Parts of the brain that help to process information and form memories- sensory information.
An association area in the frontal lobe related to language production.
When patients with damage to Broca's area were able to understand speech but had trouble producing it.
The area of the frontal lobe bordering the parietal lobe related to movement and control of body’s muscles.
Railroad construction foreman who survived an explosion which shot a tamping rod through his left frontal cortex. His personality changed after: from being a stable, steady temperament to being immature, moody, and angry.